Prostate test that is 90% accurate

Last updated at 08:59 17 October 2006

A new genetic test that is more than 90 per cent accurate should end "agonising uncertainty" for thousands of men with signs of prostate cancer - and make a national screening programme for the disease a real possibility for the first time.

Cancer of the prostate, the walnut-sized gland at the base of the bladder that produces semen, kills over 10,000 men a year, making it the second most common cause of male cancer deaths in the UK.

In recent years, demands have grown for a screening programme, similar to mammography and smear tests to pick up early cancers in women.

Yet the only diagnostic method available on the NHS - a blood test for the protein, Prostate Specific Antigen (PSA) - is unsatisfactory and many doctors advise men against being routinely tested.

"The problems with PSA is that high levels can be simply a sign of age, the natural size of prostate and benign prostate disease as well as cancer," explains Roger Kirby, professor of urology at St George's Hospital, London.

"As a result, a substantial number of men every year go on to have one or more negative biopsies."

"Doctors remove a small piece of prostate tissue under local anaesthetic, examine it for cancer cells, and yet reach no conclusive result."

"These men are left in limbo, not knowing whether they have a cancer inside them. It causes whole families agonising anxiety and uncertainty."

The gene, PCA3, first identified ten years ago, is only found in the prostate and increases by an average 34 times when a cancer develops.

The new genetic test is carried out on a urine sample, collected after the prostate has been lightly massaged.

Researchers, reporting an assessment of its efficacy in 1,000 men at the American Urological Association in May, hailed it as "a specific and accurate prostate cancer marker."

Alan Sherman, a 58-year-old optometrist from Chiswick, West London, has had high PSA levels for ten years during which time he has undergone several "fairly unpleasant" biopsies, all of which have been negative.

"I seem to be one of a group of men who test positively for prostate cancer but don't have the disease," says Mr Sherman.

"The problem is that once your doctors have identified a high PSA level, they can't really ignore it."

Earlier this year, he became one of the first Britons to be tested for the PCA3 gene at the privately run Prostate Centre in Wimpole Street, London.

It is one of the few centres offering the test, now available through Bostwick Laboratories in High Wycombe, Buckinghamshire, which opened last year.

For Mr Sherman, the test has brought a final all-clear from his doctors and an end to the biopsies.

"As long as I continue to have raised PSA, I'll be kept under supervision," he says.

"But the biopsies have finished and the uncertainty has gone. I feel so much more relaxed."

The test won't end all the uncertainty for middle-aged men, warns the Prostate Cancer Charity.

"More men die with prostate cancer than from it," says Chris Riley, its head of policy.

"Even when the diagnosis is crystal clear, the way forward for treatment isn't necessarily as clear."

The PCA3 test has not yet been approved for use in the NHS or by the Food And Drug Administration in the U.S., although plans to run a large multi-centre trial, in several countries including the UK, should change that within the next year or so.

"This is a very promising development and it looks as though it will bring huge reassurance to many people and better targeted treatment to men with prostate cancer," says Prof Kirby.